Pre-existing approaches to engine braking require additional components, as well as additional machining processes related to the cam lobe profiles. The additional braking rocker and lobe used in conventional systems also take up axial space along the camshaft which is sometimes required for future technologies, such as axial cam shifting or other variable valve train actuation. Some approaches use an additional braking rocker arm and an additional braking lobe.
The typical engine braking functionality is achieved by adding a third rocker arm as well as a third cam lobe to the valve train system. In such a case, the system would comprise two exhaust rocker arms, two exhaust lobes, one exhaust braking arm, and one braking lobe. An improved system with fewer components and more compact design is needed.